Never signed up but google searches for certain subjects have landed me there many times.
It has been useful for generating ideas, seeing what others have done with certain products, and just wanting to see photos of something you have an interest in. The digital equivalent to buying a bunch of magazines for ideas, such as interior design. I used it most to find examples of Ikea kitchen cabinet configurations and finish work from users of that product in their homes. It’s very useful for research in that way.
Bingo!!
Why use Pinterest when there are internet search engines which give you MORE results?